It was a rare — indeed unique — occasion when I was able to put Ritchie right. A 19th-century inventor, William Henry James Grout, did in fact design a folding wheel. His bike, predictably named the Grout Portable, had a frame. that split into two and a larger wheel that could be separated into four pieces. All the bits fitted into Grout’s Wonderful Bag, a leather case.
G.rout’s aim: to solve the problems of carrying a bike on a train. Now doesn’t that sound familiar? Grout intended to find a way of making a bike small enough for train travel: his bike was a huge beast. And importantly, the design of early bicycles gave him an advantage: in Grout’s day, tyres were solid, which made the business of splitting a wheel into four separate parts relatively simple. You couldn’t do the same with a wheel fitted with a one-piece inflated (充气的) tyre.
So, in a 21st-century context, is the idea of the folding wheel dead? It is not. A British design engineer, Duncan Fitzsimons, has developed a wheel that can be squashed into something like a slender ellipse (椭圆). Throughout, the tyre remains inflated.
Will the young Fitzsimons’s folding wheel make it into production? I haven’t the foggiest idea. But his inventiveness shows two things. First, people have been saying for more than a century that bike design has reached its limit, except for gradual advances. It’s as silly a concept now as it was 100 years ago: there’s plenty still to go for. Second, it is in the field of folding bikes that we are seeing the most interesting inventions. You can buy a folding bike for less than £1,000 that can be knocked down so small that it can be carried on a plane — minus wheels, of course — as hand baggage.
F.olding wheels would make all manner of things possible. Have we yet got the magic carpet of Andrew Ritchie’s imagination? No. But it’s progress.
第14题:We can infer from Paragraph 1 that the Brompton folding bike .
A. was portable
B. had a folding wheel
C. could be put in a pocket
D. looked like a magic carpet
[单选题]阅读文章回答第61~64题B RichardSolo 1800 Rechargeable BatteryIn just minutes a day, plug in and charge your iPhone quickly!Just plug RichardSolo 1800 into your iPhone once or twice a day, for fifteen minutes, and keep your iPhone charged up. At your desk, or
[单选题]阅读文章回答第65~68题C People diet to look more attractive. Fish diet to avoid being beaten up, thrown out of their social group, and getting eaten as a result. That is the fascinating conclusion of the latest research into fish behavior. by a team of Austra
[单选题]D.A.ndrew Ritchie, inventor of the Brompton folding bicycle, once said that the perfect portable bike would be “like a magic carpet…You could fold it up and put it into your pocket or handbag”. Then he paused: “But you’ll always be limited by the siz
[单选题](69-72题共用题干)第69题:
[单选题](69-72题共用备选答案)第69题:
[单选题]根据下列文章回答,21~25题。H.abits are a funny thing. We reach for them mindlessly, setting our brains on autopilot and relaxing into the unconscious comfort of familiar routine. “Not choice, but habit rules the unreflecting herd,” William Wordsworth said in t
[单选题]根据上文,回答 69~72 题。A.pvAB.pvpC.pEgD.丙烯酸树脂E.微晶纤维素第 69 题 肠溶性包衣材料( )
[单选题]根据上文,回答 69~72 题。A.粉体润湿性B.粉体吸湿性C.粉体流动性D.粉体粒子大小E.粉体比表面积第 69 题 接触角用来表示( )。
[单选题]根据上文,回答 69~72 题。A.药物一般以分子.胶体.无定型和微晶态等状态存在于载体材料中,可用研磨法制备B.高分子组成的固态胶体粒子,粒径多在10~1000nm范围内C.可形成分子囊D.用高分子材料将固态或液态药物包裹而成药库型的制剂E.将药物包封于类脂质双分子层内而形成的微型泡囊第 69 题 微囊( )
[单选题]根据下列选项,回答 69~72 题:A.化瘀止血B.涩肠止带C.敛肺涩肠D.补脾止泻E.补肾助阳第69题:椿皮的功效是( )